Unlocking the Oxidative Performance of Peracetic Acid: A Comprehensive Review of Activation Pathways and Mechanisms for Environmental Remediation

The activation of peracetic acid (PAA) to generate highly reactive species has emerged as a promising advanced oxidation process (AOP) for the degradation of refractory organic pollutants. This review systematically summarizes the recent advancements in PAA-based AOPs, encompassing various activation strategies, underlying reaction mechanisms, and applications across different environmental matrices. The activation methods are critically discussed, including direct energy activation, homogeneous catalysis, and heterogeneous catalysis. The generation process of diverse reactive species, like hydroxyl radicals (HO·), organic radicals (CH₃C(O)O·, CH₃C(O)OO·), and singlet oxygen (¹O₂), was introduced, and their oxidation selectivity and anti-interference ability were compared. Furthermore, the practical applications of PAA-based AOPs in treating wastewater, groundwater, and contaminated soil/sediments are reviewed. Finally, this review outlines critical challenges, including potential toxic byproduct formation, catalyst stability, and economic feasibility, and proposes future research directions to facilitate the transition of PAA-based AOPs from laboratory-scale research to full-scale implementation. This review provides insights for developing efficient, selective, and sustainable oxidation technologies, thereby contributing to the mitigation of emerging contaminant threats and the advancement of environmental remediation practices.